The first challenge one might theoretically confront when discussing gangs is trying to arrive at a suitable definition for what constitutes a gang. In fact, if a jurisdiction fails to exercise due care in defining gangs in its municipal ordinances, it may well deem as gang members a collection of weekend poker players or some other relatively crime-free assemblage and—as some cities have learned—find itself being sued.

Perhaps a good approach when seeking to characterize what constitutes gang behavior is to adopt the definition provided in Title 18, Sec. 521 of the United States Code, where “criminal street gangs” are defined for federal purposes as “ongoing groups, clubs, organizations, or associations of five or more individuals that have as one of their primary purposes the commission ...